Aya, a 33-year-old office worker, finds herself battling a growing sense of sexual frustration. It's been eight years since her last relationship, and while she longs for intimacy and connection, society still tends to shame women who openly express their desires. One night, her charming and flirty supervisor, Dojima, invites her out for drinks. Recently divorced, he shares his candid view — he’s not looking for love, just a one-night stand. This sparks something in Aya. To avoid emotional fallout or regret, she creates a set of personal rules for engaging in a one-night stand — and sets out to turn her “one-night rule” into reality.